Spring seat



Oct. 20, 1959 J, STERNl ETAL l *2,909,216

SPRING SEAT original Filed oct. 5.' 1953 Oct. 20, 1959 1 1 STERN ETAL2,909,216

SPRING SEAT Original Filed Oct. `5, 1953 2 Sheets-Sheet 2 INVENTORS,

l LEWIS J. STERN,

By HARLAN L. DAVIS @we Wfym; ffm/ Arrow/EVS 2,909,216 `'SPRING SEATLewis J. Stern, Adrian, and Harlan L. Davis, deceased, late of Clinton,Mich., by Hildred L. Davis, administratrix, Clinton, Mich., assignors toStubnitz-Greene Spring Corporation, Adrian, Mich., a corporation ofMichigan Continuation of application Serial No. 384,298, October 5,1953. `This application September 3, 1957, Serial No. 681,864

1 Claim. (Cl. 15S- 179) This invention relates to seat springs. Theobjective of automobile manufacturers and body builders in recent yearshas been to secure a seat spring with minimum depth and great economy inmanufacture and assembly. To this end many manufacturers of automobileshave adopted the so-called zig-zag Stringer type of spring in place ofthe hour-glass type of spring that has been used for many years. manyshortcomings, among which are breakage and loss of comfort for therider. the rider in hammock-like fashion so that when the limit ofstretch is reached in the stringers, there is no yield.

Maurice Stubnitz has undertaken to secure not only economy inmanufacture but to do away with the disadvantages of the zig-zag springby using .a double deck spring with coil springs with approximatelyhalf'the length of the conventional hour-glass type spring. A floatingspring wire deck is supported on the seat frame by means of spring wirestringers with loops of the safety pin type at one or both ends. Such aseat spring is described and broadly claimed in the Maurice StubnitzPatent No. 2,642,292, dated June 23, 1953.

IIt is the object of our invention to obtain substantially the goodqualities of Stubnitz double deck spring, but with much greater economyin manufacture and also economy and ease in installing the wire springassembly in the seat frame in the body of a car. To this end we proposeto build a seat bottom or seat back spring of short conical springsinterlaced with stringers which form a mat of carbon steel wire whichhas properties intermediate between the high carbon spring wire used inspring wire stringers of the prior art and the so-called basic wire.Basic wire is known as 1008 or .08 carbon. Spring wire runs .55 to about.80 carbon. It has lots of 'spring action but cannot be welded. What Ipropose is to construct the mat of wire called 1018 which means .18carbon. This wire can bewelded and this enables the wires of the mat tobe welded at the intersections, and it also enables the ends of the wireloops which support the mat in elevated position to be welded to theseat frames whet'her they be tubular, channel, angle or otherwise.

We have found that a spring so designed and so constructed is veryeconomical to manufacture and install. The areas of the mat which areundergoing a load are free to yield in these local areas in such a wayas to give the necessary yield and dampening action without the matyielding as a unit, so that no safety pin type springs are required onone or both ends of the cross stringers, as is the case in the assemblydescribed in the Stubnitz seat spring. This results in considerablesaving over the Stubnitz spring by eliminating higher cost spring Wireand the safety pin or jack spring type of Stringer ends. Themanufacturing cost is greatly reduced for the reason that costly andintricate machinery is required to manufacture these stringers with thejack spring ends, as will be apparent by examining the Medendorpapplication, Serial No. 14,942, tiled March 10, 1951. The

The zig-zag spring supports' This zig-zag spring it cheap, but it has2,909,216 .Patented Oct. 20, 1959 ends of the stringers that are to vbefastened to the seat frame can beformed .simply by a punch pressoperation.

. Referringto the drawings:

Fig. 1v isla plan view `of a seat bottom with the upholstery broken awayto aord a plan view of the seat spring. Fig. 2 isV a detail showing howthe stringers engage at thewire intersections. i i

. Fig. 3 is an end view of the seat cushionwith the upholstery brokenaway to show in-cross section the seat `frame and the wirespringassembly. l

Fig. 4 is a fragmentary sectional detail of my seatv spring assemblywith aY seat-frame constructed of Wire.

, Fig. 5 is a similar view showingthe assembly with a channel frame. l

Fig. 6is a similar view showing a tubular frame with the Stringerfeethooked in place.A

Fig. 7 is a fragmentary plan view of the set-up shown in Fig. 6.

1 designates the trimming material for the seat cushion, 2 is thepadding, and 3 is the tubular seat frame. The seat assembly has aplurality of short conical loadsupporting springs 4. These springs havecoils of diminishing diameter and size from top to bottom andconsequently these can overlap without any collision and less noise thanthe conventional type hour-glass springs. The top outer coils by reasonof the large diameter, readily yield While the inner or lower coils byreason of a small diameter are much stiffer and will resist when theforces of the load are transferred to the local areas of the mat ordeck. A border frame of wire is clipped to the outside coiled springsand small diameter tractile springs tie the springs together at theirtops.

The deck is made up of cross stringers 5 constructed as above stated ofthe 1018 wire which is wire made of steel containing approximately '.18carbon. This wire or* steel may be readily spot welded as at 6 to theframea tubular frame as shown in Fig. 3, a wire frame as shown in Fig.4, a channel frame as shown in Fig. 5,Y or any other type steel frame.The longitudinal stringers. are designated 7 and are 1018 steel wire.The coil springs are screwed into the mat at the intersections as shownat 8 in Fig. 3. The end of the coil has a notch 9 pressed into it tosnap over the longitudinal Stringer 7' and lock the spring in placeafter it has been screwed in- If it is desired to make a Stringer matwithout any possibility of the stringers and the carbon coil springsslipping or yielding, the intersecting wires can be spot welded as shownat 10 in Fig. 2.

The legs of the load-supporting cross stringers are designated 11 andthe feet 12. The legs and feet fornn L-shaped ends for the stringers. Ifit is desired to hook the end of the stringers into the frame as shownin Figs., 6 and 7, the-feet 12 have lateral spurs 13 which form;Z-shaped feet that can be hooked in holes 14 of the framer The assemblyshown in Fig. 3, is a Very advantageous one. A wire constructed of this.18 carbon steel or basic steel wire is provided with a succession ofloops 14- These loops are spot welded at 15 to the frame and this:

drops the main run of the wire down to the bottom level of the seatframe, but the main run of the wire is spaced. from the seat frame;consequently, the trimming material may be drawn under the tubular frameand secured to this drop frame by means of hog rings 16. This whole: jobmakes for a cheap spring wire assembly, an easy.'r and a cheapinstallation in seat frame, and is cheap andi eicient in the fasteningof the upholstery under the seat.: spring assembly and to the seatframe.

The L-shaped legs and feet make an effective spacer' of the wire mat ordeck'from the seat frame but alord little yield. The yield is alorded inthe interior of a. mat by these 1018 carbon wire stringers that havetheir greatest yielddin the local areas where the pressure of n the loadis the greatest.

This application is a continuation of application Serial No. 384,298,tiled October 5, 195.3, noW abandoned..

We' claim: v A relatively thin spring cushion comprisingrvincombination, a bottom frame defining the externaldimensionsof saidcushion, a deck offset above said frame, said deck being comprised of aplurality of cross stringers and a plurality o f longitudinal stringersintersecting-said cross stringers, said stringers being formed ofrelatively soft steel wire having a carbon content far below that of*spring steel andin an amount no greater than the order of about 0.18percent, and deck supporting means defining said offset andincludingVfeet on said stringers which may be welded to -saidframe,`a plurality ofhalflength high-carbon coil'springs secured to said deck at said pointsof intersection, said deck-supporting means being such as'to preventsubstantial movement ofthe peripheral edge of said deck toward itscenter and as to 4 prevent substantial inward deection of the deck as awhole, the softness of said strngers allowing local'deection of saiddeck at said points of intersection where pressure is localized by saidhalf coils, as distinguished from bodily movement of the deck as awhole, whereby said cushion combines the high resilience given by thehigh-carbon coils and the damping eect of said soft steel Wire whichcomprises said deck.

References Cited in the le of thisv patent UNITED STATES PATENTS 434,794Leggett Aug. 19, 1890 853,380 Stedman May 14, 1907" Y 887,111- McPhersonMay 12, 1908 1,663,001 Chesley Mar. 20, 1928 2,125,519 Oldham l Aug. 2,1938 2,260,954 Robinson Oct. 28,1941 2,642,929 Stubnitz June 23, 1953

